|
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | BUGS | FILES | SEE ALSO | AVAILABILITY | COLOPHON |
MCOOKIE(1) User Commands MCOOKIE(1)
mcookie - generate magic cookies for xauth
mcookie [options]
mcookie generates a 128-bit random hexadecimal number for use with
the X authority system. Typical usage:
xauth add :0 . `mcookie`
The "random" number generated is actually the MD5 message digest of
random information coming from one of the sources /dev/urandom,
/dev/random, or the libc pseudo-random functions, in this preference
order.
-f, --file file
Use this file as an additional source of randomness. When
file is '-', characters are read from standard input.
-m, --max-size number
Read from file only this number of bytes. This option is
meant to be used when reading additional randomness from a
file or device.
The number argument may be followed by the multiplicative
suffixes KiB=1024, MiB=1024*1024, and so on for GiB, TiB, PiB,
EiB, ZiB and YiB (the "iB" is optional, e.g., "K" has the same
meaning as "KiB") or the suffixes KB=1000, MB=1000*1000, and
so on for GB, TB, PB, EB, ZB and YB.
-v, --verbose
Inform where randomness originated, with amount of entropy
read from each source.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
It is assumed that none of the randomness sources will block.
/dev/urandom
/dev/random
md5sum(1), X(1), xauth(1), rand(3)
The mcookie command is part of the util-linux package and is
available from Linux Kernel Archive
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.
This page is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found at
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
bug report for this manual page, send it to
util-linux@vger.kernel.org. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2017-07-05. If you discover any rendering problems in this HTML ver‐
sion of the page, or you believe there is a better or more up-to-date
source for the page, or you have corrections or improvements to the
information in this COLOPHON (which is not part of the original man‐
ual page), send a mail to man-pages@man7.org
util-linux December 2014 MCOOKIE(1)